The bit is designed for drilling of medium-hard abrasive rock formations, e.g. hard limestone and shale, dolomite, magnesite, ferrous quartzite, diorite, quartzeous porphyry, solicited shale, fine-grained skarn, weak pegmatite, martite ore and metamorphic granite rocks, most frequently found in gold, granite and copper mines.
Recommended drilling parameters for maximum efficiency of the bit: low and medium rotation speed (60-115 RPM) and axial load from 60 to 170 kN.
Rock strength range - from 24 000 to 44 000 PSI.
Bit diameter, mm | 215.9 |
Bit diameter, inch | 8 ½ |
Bit designation, IADC | 612X |
Connection thread, API | 4 ½" REG |
Bearing type | Air-cooled, on rolling bearings |
Formation type | For medium-hard abrasive formations |
Rotation speed. RPM | 115-60 |
Max. applicable load, kN | 60-170 |
Weight, kg | 33.9 |
Bearing/cooling type | Roller – Ball – Roller / Air cooling |
Blow-through type | Side / center |
Cutting structure | Tungsten carbide inserts |